Selective Laser Melting

A miniaturized selective laser melting (miniSLM) device was developed to perform operando X-ray diffraction and imaging experiments at the Swiss Light Source.  The device exhibits the full functionality of a commercial SLM device.

3D rendered view of the miniaturized SLM machine

A collimated infrared laser beam is deflected by a 2-axis scanning unit into the main chamber. The laser beam is focused onto a 12 × 12 mm2 build stage that can be translated vertically with a travel range of 12 mm and sub-micron step size. The build stage can be heated using a silicon-nitride resistive heater. Powder recoating is based on a hopper feeding system. The powder reservoir can be moved across the baseplate with the aid of a motor-spindle assembly. The device is completely closed, preventing laser light or particles to escape. The chamber is continuously flushed with high purity argon gas. With the aid of manual flowmeters, a slight overpressure is created in the chamber to avoid oxygen contamination by the outside atmosphere. The whole setup (laser, scanning unit and printing chamber) is cooled down with a closed-loop air-water exchange based chiller.  The video below describes the basic principle behind  operando X-ray diffraction during SLM. 

  Type redPOWER® continuous wave Fiber Laser
  Wavelength 1070nm
  Maximum power 500W
  Spot size 25 µm - 250 µm
  Max scanning speed > 2000mm/s
  Dimensions 15mm x 20mm x 30mm
  Build plate 12mm x 12mm
  Maximum build height 8mm
  Maximum temperature 150°C
  Maximum angle tilt stage 20°


Basic principle of operando X-ray diffraction during selective laser melting.
(Credit: Paul Scherrer Institute/Mahir Dzambegovic)